1. Field of the Invention
The present invention relates to a solid state imaging device having a plurality of photoelectric conversion portions arranged above a substrate and color filters formed above the plurality of photoelectric conversion portions, respectively.
2. Description of the Related Art
In JP-T-2002-502120 (FIG. 5B), there is disclosed a solid state imaging device configured so that a lower electrode is formed on a Si substrate, a photoelectric conversion film is formed of an organic photoelectric conversion material on the lower electrode, upper electrodes divided for every pixel are formed on the photoelectric conversion film, and color filters divided for every pixel are formed on each of the upper electrodes. According to the solid state imaging device as mentioned above, it is possible to increase light receiving areas of pixels, and thus it is possible to increase sensitivity, as compared with a single plate type solid state imaging device that has been the mainstream until now. In addition, since the entire Si substrate can be used for a circuit of reading out signals based on electric charges generated from the photoelectric conversion film, it is possible to increase the number of pixels even when a decrease in size of the circuit is not achieved.
In WO01/082390 (FIG. 4), there are disclosed an organic EL display configured so that a polymer film is formed on an organic light emitting element array in order to protect organic light emitting elements, and an oxide film is formed on the polymer film by an atomic layer deposition (an ALD method). Since the ALD method makes it possible to form a dense inorganic layer, it is possible to prevent permeation of foreign substance, moisture, or the like into the organic light emitting element, and thus it is possible to prevent performance deterioration of the organic light emitting element.
In a solid state imaging device disclosed in JP-T-2002-502120 (FIG. 5B), since the organic material is used as a photoelectric conversion film, there is concern about characteristic deterioration of the photoelectric conversion film. Accordingly, it is considered that it is effective to use the oxide film formed by the ALD method as described in WO01/082390 (FIG. 4) as a passivation film of the photoelectric conversion film. However, for example, when a metallic oxide and the like having high density are intended to be formed as an oxide film, and when the metallic oxide film is intended to be formed by the ALD method, there is a need to use ozone as a gas therefor. Thus, there is concern about occurrence of deterioration and degeneration caused by the ozone in the upper electrodes and the photoelectric conversion film. As described in WO01/082390 (FIG. 4), even when the polymer film is formed and the ALD method is performed, it is not possible to avoid the problems, that is, the degeneration and deterioration. Accordingly, it is an important object to avoid the problems in order not to deteriorate performance of the solid state imaging device.